JP2018535817A - Bismuth compounds containing perfluoroalkyl groups as Lewis acid catalysts - Google Patents

Abstract

  The present invention relates to bismuth compounds containing perfluoroalkyl groups as Lewis acid catalysts, to specific compounds and to processes for their preparation.

Description

  The present invention relates to bismuth compounds containing perfluoroalkyl groups as Lewis acid catalysts, to specific compounds and to processes for their preparation.

  Catalytic reactions using Lewis acids are a wide range of methods of significant importance for organic synthesis and industrial preparation of various materials. Numerous important industrial processes catalyzed by Lewis acids include, for example, Friedel-Craft alkylation and acylation of aromatic compounds, Gutterman-Koch reaction, Beckman and Fries rearrangement, Mukaiyama aldol condensation [Acid Catalysis in Modern Organic Synthesis, H. Yamamoto and K. Ishihara (edit), WILEY-VCH, Weinheim, 2008].

G. N. Lewis defines acid as a substance that can act as an electron pair acceptor. According to this definition, a Lewis acid is an electron-deficient molecule or species. Commonly used Lewis acid catalysts such as AlCl ₃ , TiCl ₄ , ZnCl ₂ , and BF ₃ diethyl etherate are moisture sensitive and generally cannot be recovered after completion of the reaction.

Further well known Lewis acids are bismuth salts (eg BiCl ₃ , BiBr ₃ and Bi (OSO ₂ CF ₃ ) as described in T. Ollevier, org. Biomol. Chem., 2013, 11, 2740-2755. ) ₃ ). However, when BiCl ₃ is used as a catalyst, a high concentration, generally 10 mol%, is required and, for example, when a steel vessel is used, the liberation of HCl can lead to corrosion of the reactor. The most well-known bismuth catalyst is bismuth triflate. The disadvantage of this compound is its sensitivity to hydrolysis in the presence of water and reactivity with alcohols and amines.

FHA Kwie et al, Synthetic Communications, 40, 2010, 1082-1087 or TC Wabnitz et al, Chem. Eur. J. 10, 2004, 484-493 is any trifluoromethanesulfonic acid (CF ₃₎ released from bismuth triflate. SO ₃ H) also describes that it can cause catalytic reactions.

  S. Kobayashi et al, Chem. Eur. J., 12, 2006, 5954-5960, wherein Bi (III) salts are stabilized using organic ligands such as 2,2′-bipyridine derivatives. Propose to get.

R. Qiu et al, Adv. Synth. Catal, 352, 2010, 153 reports the use of bismasperfluorooctane sulfanate as a catalyst.
Therefore, there is a continuing need for alternative Lewis acid catalysts in order that reactions catalyzed by Lewis acids can be optimally performed.

The object of the present invention is therefore to develop an alternative Lewis acid catalyst which makes it possible to carry out the reaction to be catalyzed in good yield.
Surprisingly, it has been found that certain bismuth compounds containing perfluoroalkyl groups are catalytically active and indeed are more catalytically active than BiCl ₃ .

W. Tyrra et al, Can. J. Chem., 1989, 67, 1949-1951, and D. Naumann et al, J. Organomet. Chem., 1987, 334, 323-328 are bismuth compounds, Bi (CF _{3) 3, Bi (CF 3} ) 2Cl, Bi (CF 3) Cl 2, Bi (CF 3) 2F, Bi (C 2 F 5) 3, Bi (n-C 3 F 7) 3, Bi (n- _{C 4 F 9) 3, Bi} (n-C 6 F 13) 3, and _{Bi (n-C 8 F 17} ) are ₃ disclose. Application of these compounds was not described.

S. Pasenok et al, J. Organomet. Chem., 1991, 417, C47-C49 discloses the compounds diphenyl (trifluoromethyl) bismuth and phenylbis (trifluoromethyl) -bismuth. The compound is prepared by reaction of Cd (CF ₃ ) ₂ · 2CH ₃ CN with phenyl bismuth halide. The compound has been described as air sensitive.
NV Kirij et al, J. Fluorine Chem., 1994, 69, 219-223 similarly describes aryl (trifluoromethyl) bismuth compounds (aryl group changed) and their reaction with benzoylpyridinium chloride I'm doing it.

The invention therefore firstly relates to the use of at least one compound of formula (I).

M here represents, in each case, independently of one another, 2, 3 or 4;
n represents 1, 2, or 3; and
X represents F, Cl, Br, or OSO ₂ CF ₃ as a Lewis acid catalyst.

In a preferred embodiment of the invention, the perfluoroalkyl group (C _m F _{2m + 1} ) is preferably identical at each occurrence.
Therefore, as described above, the present invention further relates to the use of at least one compound of formula (I), wherein the perfluoroalkyl group (C _m F _{2m + 1} ) is identical on each occurrence. is there.

The perfluoroalkyl group (C _m F _{2m + 1} ) (where m is 2, 3, or 4) is preferably pentafluoroethyl, n-heptafluoropropyl, iso-heptafluoropropyl, n-nanofluorobutyl, secondary- Nanofluorobutyl or tertiary-nonafluorobutyl. The perfluoroalkyl group (C _m F _{2m + 1} ) particularly preferably represents pentafluoroethyl or n-nonafluorobutyl.
Thus, as described above, the present invention further relates to the use of at least one compound of formula (I), wherein the perfluoroalkyl group (C _m F _{2m + 1} ) is pentafluoroethyl or n-nonafluorobutyl. Show.

In a further preferred embodiment of the invention, compounds of formula (I) are used wherein n is 1 or 2. Preferred compounds of formula (I) in the use of Lewis acid catalysts are those in which X represents Cl.
The invention therefore furthermore relates to the use of at least one compound of formula (I) as described above and preferably wherein X represents Cl.

The invention further relates to a compound of formula (I) as well.

M here represents, in each case, independently of one another, 2, 3 or 4;
n represents 1 or 2; and
X represents F, Cl, Br, or OSO ₂ CF ₃ .
Preferred compounds of formula (I) in which n represents 1 or 2 are those in which X represents Cl or F.

Particularly preferred compounds of the formula (I) in which n represents 1 or 2 are those in which X represents Cl.
The present invention therefore further relates to a compound of formula (I), characterized in that, as described above, X represents Cl.

Particularly preferred compounds are those compounds of formula (I) in which X represents Cl and m represents 2 or 4. Very particular preference is given to compounds of the formula (I) in which X represents Cl and m represents 2.
Very particularly preferred Lewis acid catalysts are the compounds Bi (C ₂ F ₅ ) ₃ , Bi (C ₂ F ₅ ) Cl ₂ , and Bi (C ₂ F ₅ ) ₂ Cl.

Compounds of formula (I) in which n represents 3 are cadmium complexes as described, for example, in D. Naumann et al, J. Organomet. Chem., 1987, 334, 323-328, or D. Naumann It can be prepared based on known synthetic methods using zinc complexes as described in et al, J. Fluorine Chem. 1994, 66 (1), 79-80.
However, cadmium complexes are disadvantageous starting materials from an economic point of view.

The invention therefore further relates to a process for the preparation of a compound of formula (I) wherein n is 3 as described above, and features a compound of formula (II).

Where m represents 2, 3, or 4 and reacts with bismuth trichloride or bismuth tribromide, preferably bismuth trichloride, where the reaction conditions are water content and even oxygen content up to 100 ppm. It is selected by such a method.

As described above or below, the reaction takes place in an inert gas atmosphere with an oxygen content of up to 100 ppm. It is particularly preferred if the oxygen content is less than 100 ppm, very particularly preferably up to 50 ppm. The water content of the reagent and inert gas atmosphere is up to 100 ppm. It is particularly preferred if the water content of the reagent and atmosphere is less than 100 bpm, very particularly preferably 5-50 ppm.
As described below, the conditions regarding water content and oxygen content do not apply to work-up after successful reaction of compounds of formula (II) or compounds of formula (IIIa) and (IIIb).

As an alternative to the compound of formula (II), it is possible to use a Grignard reagent, which conforms, for example, to formula (IIA).

M here represents 2, 3, or 4 and Y represents I or Br. In addition, the reaction conditions described for the reaction with the compound of formula (II) (water content and furthermore the oxygen content should be up to 100 ppm) are also compatible with the reaction of the compound of formula (IIA). Applied.

Compounds of formula (IIA) can be prepared based on known synthetic methods.
Bismuth trichloride, bismuth tribromide, and bismastristriflate are commercially available.

Compounds of formula (II) can be prepared based on known synthetic methods.
As described in the Examples section, a variant of the synthesis of the compound of formula (II) is the modification of the corresponding monohydride perfluoroalkene (HC _m F _{2m + 1} ) in dry diethyl ether and n-butyllithium in pentane. Reaction with 2M solution.
Alternatively, the compound of formula (II) is prepared from perfluoroalkyl iodide as described in N. Yu. Adonin et al, Z. Anorg. Allg. Chem., 2007, 633, 647-652. Can be done.
As mentioned above, for further reaction of the compound of formula (II) with bismuth trichloride, bismuth tribromide, or bismastristriflate, the reaction is preferably carried out without further purification.

Alternatively, as described in the Examples section, compounds of formula (II), tris (perfluoroalkyl) phosphine _{(P (C m F2 m +} 1) 3) and the n- butyllithium 1.6M solution in hexane Can be prepared by the following reaction. As mentioned above, for further reaction of the compound of formula (II) with bismuth trichloride, bismuth tribromide or bismuth triflate, the reaction is preferably carried out without further purification.

The reaction with bismuth trichloride is carried out directly in the solvent or solvent mixture present, as described above, after the in situ preparation of the compound of formula (II).
The starting materials are preferably mixed at low temperatures, for example at temperatures between -100 ° C and -65 ° C. The mixture is then warmed to a temperature between -10 ° C and 5 ° C, preferably 0 ° C. The reaction mixture is then filtered under an inert gas atmosphere.
This is preferably followed by a suitable purification method. For example, washing the residue with a suitable solvent and subsequent sublimation.

The invention further relates to a process for the preparation of a compound of formula (I) wherein n represents 1 or 2 and features a compound of formula (II).

Where m represents 2, 3, or 4 independently of each other in each case, and in the first reaction is reacted with dichloroarylbismutan or chloro (diaryl) bismutan, wherein aryl in the corresponding bismutan Have 6 to 10 carbon atoms (which may be substituted or unsubstituted) and are of formula (IIIa) or (IIIb)

The intermediate of is then reacted with hydrogen chloride, hydrogen bromide, anhydrous HF, or trifluoromethanesulfonic acid to give a compound of formula (I), wherein Ar in each case, independently of each other, 6 Represents an aryl group having from 10 to 10 carbon atoms (which may be substituted or unsubstituted), and wherein the conditions for the reaction with the compound of formula (II) are such that the water content and further the oxygen content is , Up to 100 ppm.

As an alternative to the compound of formula (II), it is also possible to carry out this reaction using a Grignard reagent, which conforms, for example, to formula (IIA).

M here represents 2, 3, or 4 and Y represents I or Br. In addition, the reaction conditions described for the reaction with the compound of formula (II) (water content and furthermore the oxygen content should be at most 100 ppm) also correspond to the reaction of the compound of formula (IIA). Applied.

The present invention further relates to compounds of formula (IIIa) and (IIIb) as well as the same.

Where m represents 2, 3 or 4 independently of each other in each case, and Ar independently represents an aryl group having 6 to 10 carbon atoms in each case. And it may be substituted.

An aryl group having 6 to 10 carbon atoms represents phenyl or naphthyl, which may be mono- or polysubstituted by alkyl, fluorinated alkyl, Oalkyl, or N (alkyl) 2.
“Alkyl” refers to a straight-chain or branched alkyl group having 1 to 10 carbon atoms.
“Fluorinated alkyl” is a straight chain having 1 to 10 carbon atoms (at least one H atom of a straight or branched alkyl group having 1 to 10 carbon atoms has been replaced with an F atom). Or a branched fluorinated alkyl group. It is also possible that all hydrogen atoms are replaced by F atoms.

  The aryl group is preferably phenyl which is unsubstituted or monosubstituted by alkyl, fluorinated alkyl, Oalkyl, or N (alkyl) 2. Ar is preferably in particular an unsubstituted phenyl group or a phenyl group monosubstituted by alkyl. Ar is preferably very particularly an unsubstituted phenyl group.

Linear or branched alkyl groups having 1 to 10 carbon atoms are, for example, methyl, ethyl, isopropyl, propyl, butyl, secondary butyl or tertiary butyl, pentyl, 1, 2, or 3 methylbutyl, 1, 1, 1, 2- or 2, 2-dimethylpropyl, 1 ethylpropyl, n-hexyl, n-heptyl, n-octyl, n-nonyl or n-decyl.
“Fluorinated alkyl” is a linear or branched fluorinated alkyl group, preferably having 1 to 4 carbon atoms. “Fluorinated alkyl” is preferably trifluoromethyl, pentafluoroethyl, heptafluoroisopropyl, heptafluoropropyl, and nonafluorooptyl, among others.

The compound of formula (IIIa) is preferably bis (pentafluoroethyl) phenylbismutan, in particular.
The compound of formula (IIIb) is preferably in particular pentafluoroethyldiphenylbismutan.
Compounds of formula (IIIa) and (IIIb) are likewise suitable as Lewis acid catalysts.

  The invention therefore furthermore relates to the use of at least one compound of formula (IIIa) or (IIIb) as a Lewis acid catalyst as described above or preferably as described above.

The invention therefore furthermore furthermore relates to a process for the preparation of a compound of formula (IIIa) or (IIIb) and features a compound of formula (II).

Where m, in each case, independently of one another, represents 2, 3 or 4 and reacts with dichloroarylbismutan or chloro (diaryl) bismutan, wherein the aryl in the corresponding bismutan is 6 Refers to an aryl group having from 10 to 10 carbon atoms, which may be substituted or unsubstituted.
As noted above, compounds of formula (II) can be prepared in situ as well.

Dichlorophenyl bismutan is commercially available.
The synthesis of dichlorophenyl bismutan and diphenyl chloro bismutane is described, for example, in S. Faleschini et al, Journal of Organometallic Chemistry, 1972, 44, 317-323, or in DHR Barton et al, Tetrahedron, 1986, 42, 3111-3122. It is described in.
The compounds dichloroarylbismutan and diarylchlorobismutan can be prepared analogously to these processes.
The reaction with dichloroarylbismutane or chloro (diaryl) bismutane, preferably the reaction of dichloroarylbismutane, is carried out in the solvent or solvent mixture present after the in situ preparation of the compound of formula (II) as described above. Is carried out directly to give a compound of formula (IIIa) or (IIIb).

The starting materials are preferably mixed at low temperatures, for example at temperatures between -100 ° C and -65 ° C. The mixture is then warmed to a temperature between -10 ° C and 5 ° C, preferably 0 ° C. The reaction mixture is then filtered under an inert gas atmosphere.
This is preferably followed by a suitable purification method for the isolation of the compound of formula (IIIa) or (IIIb). For example, washing the residue with a suitable solvent, followed by sublimation or crystallization.

For reaction with hydrogen chloride, hydrogen bromide, anhydrous HF, or trifluoromethanesulfonic acid, the isolated compound of formula (IIIa) or formula (IIIb) is first introduced and preferably degassed. The
Then hydrogen chloride, hydrogen bromide, anhydrous HF or trifluoromethanesulfonic acid is concentrated and the reaction mixture is preferably at a temperature of 0 ° C. to 70 ° C., particularly preferably at a bath temperature of 10 ° C. to 60 °. Stir. Excess hydrogen chloride or hydrogen bromide or excess HF or trifluoromethanesulfonic acid is removed by concentration, and the residue is preferably sublimated for purification.

As described above, a compound of formula (I) wherein X represents F or OSO ₂ CF ₃ or alternatively a compound corresponding to formula (I) wherein X represents Cl by reaction with AgF or AgOSO ₂ CF ₃ , Can be adjusted. The reaction is preferably carried out in an organic solvent or organic solvent mixture. A mixture of dichloromethane and acetonitrile (1: 1) is particularly preferably used. The reaction temperature is preferably room temperature. It is furthermore preferred to carry out the reaction under inert gas conditions and by exclusion of light.

The invention further relates to a Lewis acid catalyst of formula (I) or formula (IIIa) and (IIIb) for use in a Lewis acid catalyzed reaction as described above or preferably as described above.
In a preferred embodiment of the present invention, the Lewis acid catalyzed reaction includes condensation reaction, alcoholysis, aldol reaction, Mukaiyama aldol reaction, Guttermann-Koch reaction, Beckmann- and Fries rearrangement, Friedel-Craft acylation, Friedel-Craft alkylation. , Mannich reaction, Diels-Alder reaction, Azadirs-Alder reaction, Baylis-Hillman reaction, Reformatsky reaction, Claisen rearrangement, Prance cyclization reaction, allylation of carbonyl compounds, cyanation of aldehydes and ketones, aldehydes and ketones Selected from cyanosilylation, 1,3-dipolar cycloaddition, or Michael reaction.

The compound of formula (I) is preferably used in a substoichiometric amount of the catalyst of from 0.01 to 10 mol%, based on the starting materials. The compounds of the formula (I) are particularly preferably used in the amounts of 1-5 mol% as described above or preferably as described above. One skilled in the art of catalytic reaction can select the optimal amount of catalyst for the corresponding reaction to be catalyzed. The results in the Example section confirm that (C ₂ F ₅ ) BiCl ₂ and (C ₂ F ₅ ) ₂ BiCl are very more active catalysts in the Diels-Alder reaction compared to BiCl _3. doing.

As described above or preferably as described above, the choice of solvent for the Lewis acid catalyzed reaction is important due to the particular solubility characteristics of the compound of formula (I).
Suitable protic solvents for use of the Lewis acid catalyst according to the invention are ethanol or methanol.

Suitable aprotic solvents for use of the present Lewis acid catalyst according to the present invention are acetonitrile, propiononitrile, benzonitrile, nitromethane, diethyl ether, methyl tertiary butyl ether 1,4-dioxane, tetrohydrofuran, 2-methyl. Tetrahydrofuran, dichloromethane, 1,2-dichloroethane, monoglyme, diglyme, triglyme, hexane, heptane, petroleum ether, benzene, or toluene.
The class of ionic liquids is also suitable as a solvent for the use of Lewis acid catalysts according to the present invention.

  An ionic liquid is taken to mean a salt that generally consists of an organic cation and an inorganic anion. They do not contain any neutral molecules and usually have a melting point below 373 K [Wasserscheid P, Keim W, Angew. Chem. 112, 2000, 3926]. Due to their salt nature, ionic liquids have unique material properties (eg, low vapor pressure, liquid state over a wide temperature range), are non-flammable, have high electrical conductivity and high electrochemical and thermal properties. Present stability.

An ionic liquid suitable as a solvent for using the Lewis acid catalyst according to the present invention is an ionic liquid having an organic cation, and the anion thereof is [R ₁ SO ₃ ] −, [R ₂ COO] ⁻ , [R ₂ SO ₃ ] ⁻ , [R ₁ OSO ₃ ] ⁻ , [BF ₄ ] ⁻ , [HSO ₄ ] ₁ ⁻ , [(R ₁ ) ₂ P (O) O] ⁻ , [(R ₂ ) ₂ P (O ) O] ⁻ , [R ₂ P (O) O ₂ ] ₂ ⁻ , [(FSO ₂ ) ₂ N] ⁻ , [(R ₂ SO ₂ ) ₂ N] ⁻ , [(R ₂ SO ₂ ) ₃ C] ⁻ , [(FSO ₂ ) ₃ C] ⁻ , [P (R ₂ ) _y F _6−y ] ⁻ , [BF _x (R ₂ ) _4−x ] ⁻ , [BF _x (CN) _4−x ] ^{− _{, [B (R 1) a}} (CN) 4-a] -, [B (R 2) F 2 (CN)] -, or _{[B (R 2) F (} CN) 2 ^- is selected from the group consisting of,
Here, R ₁ represents in each case, independently of one another, a straight-chain or branched alkyl group having 1 to 12 carbon atoms,
R ₂ , independently of one another, represents in each case a partially fluorinated or fully fluorinated linear or branched alkyl group having 1 to 12 carbon atoms, or pentafluorophenyl. Show
x represents an integer 0, 1, 2, or 3;
y represents an integer 0, 1, 2, 3, or 4;
a represents an integer 1 or 2;

A fully fluorinated linear or branched alkyl group having 1 to 4 carbon atoms is, for example, trifluoromethyl, pentafluoroethyl, n-heptafluoropropyl, iso-heptafluoropropyl, n-nonafluoro. Optil, secondary-nonafluorooptyl, or tertiary-nonafluorooptyl.
R ₂ represents the above perfluoroalkyl group and, for example, perfluorinated n-hexyl, perfluorinated n-heptyl, perfluorinated n-octyl, perfluorinated ethylhexyl, perfluorinated n-nonyl, perfluorinated n Linear or branched perfluorinated alkyl groups having 1 to 12 carbon atoms including -decyl, perfluorinated n-undecyl, or perfluorinated n-dodecyl are defined analogously.
R ₂ is preferably trifluoromethyl, pentafluoroethyl or nonafluorooptyl, very particularly preferably trifluoromethyl or pentafluoroethyl.

The variable y is preferably 1, 2, or 3, particularly preferably 3.
Preferred solvents are anionic _{[P (R 2) y F} 6-y] - and _[R 2 _SO 3] ^- are ionic liquids with, where, or _{R 2} and y is instructed preferably indicated Has a meaning.
Particularly preferred solvents are ionic liquids with anions [P (C ₂ F ₅ ) ₃ F ₃ ] ⁻ and [CF ₃ SO ₃ ] ⁻ .

The organic cation is usually not limited and is preferably selected from an imidazolium cation, a pyridinium cation, or a pyrrolidinium cation, which may be appropriately substituted as is known from the prior art.
The ionic liquid 1-ethyl-3-methylimidazolium tris (pentafluoroethyl) trifluoro-phosphate {[EMIM] [FAP]} is very particularly preferably selected as solvent.

The following examples of Lewis acid catalyzed reactions are as described above or preferably as described above, although the use of a compound of formula (I) can similarly achieve very good yields in direct comparison with BiCl _3. , Indicating that the amount of the catalyst is greatly reduced in the case of the Lewis acid catalyst according to the invention.

  The suitability of the compounds of formula (I) as Lewis acid catalysts was confirmed by Diels-Alder reaction and cyanosilylation of aldehydes. These reaction types represent Lewis acid catalyzed reactions.

  Even without further comments, it is assumed that one skilled in the art will be able to utilize the following description to the broadest extent. The preferred embodiments and examples should therefore merely be regarded as descriptive disclosure which is in no way limiting in any way.

Example 1: Synthesis of tris (pentafluoroethyl) bismutan, Bi (C2F5) 3).

50 ml (100 mmol) of a 2M solution of n-butyllithium in pentane in 200 ml of dry diethyl ether is first introduced into a 500 ml Schlenk flask and degassed in nitrogen convection at -90 ° C. 12.3 g (102.5 mmol) of pentafluoroethane is concentrated at −80 ° C. and the mixture is stirred for 30 minutes at the same temperature. 6.31 g (20.0 mmol) of bismuth trichloride (BiCl ₃ ) is added in a convection of nitrogen. The reaction mixture is stirred for 60 minutes at −80 ° C. and warmed to 0 ° C. during 4 hours.

The reaction mixture is filtered under an inert gas atmosphere and the residue is washed twice with 20 ml of dry n-pentane each time. The reaction mixture is evaporated at static vacuum (70 mbar). Residual solvent is removed in a sublimation apparatus in a high vacuum, and the reaction product is cooled with dry ice (−50 ° C. to −30 ° C.) and sublimed to a cold finger. After warming to room temperature, 7.16 g of tris (pentafluoroethyl) bismutan, Bi (C ₂ F ₅ ) ₃ is obtained as a colorless liquid. Yield (based on bismuth trichloride): 63% (12.6 mmol).
Melting point: -10 ° C.
This NMR data corresponds to the values known from the literature [D. Naumann, W. Tyrra, J. Organomet. Chem. 1987, vol. 334, pp. 323-328].

A 1.6 M solution of n-butyllithium in hexane (0.80 ml, 1.28 mmol) was added to a 171 mg solution (0.44 mmol) of P (C ₂ F ₅ ) ₃ in Et ₂ O (10 ml) at −65 ° C. ) And the mixture is stirred for 10 minutes. 0.15 g (0.48 mmol) of BiCl ₃ is added at the same temperature and the reaction mixture is slowly warmed to room temperature. This solution is examined by NMR spectroscopy. The NMR data confirms the formation of Bi (C ₂ F ₅ ) ₃ .

Example 2: Bis (pentafluoroethyl) phenyl bis endless, preparation of _{PhBi (C 2 F 5) 2} .

22 ml (44.0 mmol) of a 2M solution of n-butyllithium in pentane in 100 ml Et ₂ O are first introduced into a 250 ml Schlenk flask and degassed at 80 ° C. 5.40 g (45 mmol) of pentafluoroethane is concentrated at −80 ° C. and the mixture is stirred for 25 minutes at the same temperature. 3.87 g (10.8 mmol) of dichlorophenylbismutan is added and the mixture is stirred in a cold bath at −80 ° C. for 3.5 hours. The suspension is filtered in an inert gas atmosphere and evaporated in a static high vacuum.

Residual solvent is removed in a high vacuum sublimation apparatus and at an oil bath temperature of 80 ° C., and the reaction product is cooled by dry ice (−35 ° C.) and sublimed to a cold finger. . Warming to room temperature gives 4.22 g of bis (pentafluoroethyl) phenylbismutan, PhBi (C ₂ F ₅ ) ₂ as a colorless liquid.
Yield (based on dichlorophenylbismutan): 8.1 mmol, 75%.
Melting point: 15 ° C.
The product is characterized by NMR and IR spectroscopy and by mass spectrometry.

Example 3: Bis (pentafluoroethyl) _{Kurorobisumutan, (C} 2 _F 5) Preparation of 2 BiCl.

4.02 g (7.7 mmol) of bis (pentafluoroethyl) phenylbismutan, PhBi (C2F5) 2) is first introduced into an 800 ml Young tap ampoule and degassed. 1.09 g (30.0 mmol) of hydrogen chloride is concentrated and the mixture is stirred at an oil bath temperature of 60 ° C. for 2.5 hours. Excess hydrogen chloride is removed by concentration and the residue is sublimed in a high vacuum at 90 ° C. to give bis (pentafluoroethyl) chlorobismutan (C ₂ F ₅ ) ₂ BiCl as a yellow solid. Yield (based on bis (pentafluoroethyl) phenylbismutan): 3.45 g (7.2 mmol, 92%). Melting point: 75-76 ° C. The product is characterized by NMR and IR spectroscopy and by mass spectrometry.

Example 4: Preparation of pentafluoroethyldiphenylbismutan, Ph ₂ BiC ₂ F ₅ .

20 ml of n-BuLi (150 mmol in n-pentane, 2M) in 150 ml of diethyl ether are first introduced into a 500 ml Schlenk flask and degassed at -80 ° C. 5.4 g (45 mmol) of pentafluoroethane is concentrated and the mixture is stirred for 10 minutes at the same temperature. 7.97 g (20 mmol) of chloro (diphenyl) bismutan is added and the mixture is stirred at −60 ° C. for 4 hours and then warmed to room temperature. All volatile components are removed in a high vacuum and the resulting residue is dissolved in n-pentane and filtered in an inert gas atmosphere and washed with n-pentane. Solvent removal gives pentafluoroethyl (diphenyl) bismutan, Ph ₂ BiC ₂ F ₅ in the form of colorless crystals, which after a short time changes color to tan. Yield (based on chloro (diphenyl) bismutan): 6.20 g (12.9 mmol, 65%).

80 ml of diethyl ether are first introduced into a 250 ml Schlenk flask and degassed at -196 ° C.
2.95 g (7.6 mmol) of tris (pentafluoroethyl) phosphine, (C2F5) 3P is concentrated and brought to 65 ° C. 9.43 g (22.2 mmol; 13.9 ml) of a 1.6M solution of n-BuLi in hexane is added to the mixture and then stirred at the same temperature for 15 minutes. 8.75 g (22.0 mmol) of chloro (diphenyl) bismutan is added to the reaction mixture and it is then warmed to 0 ° C. with stirring for 3 hours. The resulting suspension is filtered under an inert gas atmosphere, the residue is washed with a small amount of diethyl ether, and all volatile components of the filtrate are removed in a high vacuum.

The resulting residue is dissolved in 100 ml of n-pentane. The solution is evaporated until the first crystals are formed and the product is crystallized by cooling to -28 ° C. The crystals are washed with a small amount of n-pentane, dried in high vacuum and give pentafluoroethyl (diphenyl) bismutan, Ph2BiC2F5, in the form of colorless, hydrolysis-sensitive crystals. Yield (based on chloro (diphenyl) bismutan): 8.57 g (17.8 mmol. 81%).
The product is characterized by NMR and IR spectroscopy. NMR and IR data correspond to the values given in Example 4A.

Example 5: Preparation of pentafluoroethyldichlorobismutan, BiCl ₂ (C ₂ F ₅ )

6.20 g (12.9 mmol) of diphenyl (pentafluoroethyl) bismutan, Ph ₂ BiC ₂ F ₅ is dissolved in 25 ml of diethyl ether and transferred to an 800 ml Young tap ampoule. The solvent is removed in a high vacuum and 1.46 g (40 mmol) of hydrogen chloride is concentrated. The reaction mixture is stirred at an oil bath temperature of 60 ° C. for 20 hours. All volatile components are removed by concentration and the residue is dissolved in dichloromethane and transferred to a 100 ml Schlenk flask. Sublimation in high vacuum at an oil bath temperature of 90 ° C. and a cold finger temperature of −78 ° C. gives pentafluoroethyldichlorobismutan, C 2 F 5 BiCl 2 as a yellow solid. Yield (based on pentafluoroethyl (diphenyl) bismutan): 4.67 g (11.7 mmol, 91%).
Melting point: 104 ° C
The product is characterized by NMR and IR spectrometry.

Example 6: Preparation of bis (pentafluoroethyl) fluorobismutan

366 mg (2.885 mmol) of silver fluoride is added to a solution of 2BiCl (C ₂ F ₅ ) (1.38 g, 2.86 mmol) in a mixture of dichloromethane (10 ml) and acetonitrile (10 ml) in nitrogen convection. . The reaction mixture is stirred for 2.5 hours at room temperature, protected from light. The precipitated solid is filtered under an inert gas atmosphere and the filtrate is evaporated in a high vacuum. Drying in high vacuum gives (C ₂ F ₅ ) ₂ BiF as a colorless, slightly crystallized solid. The yield is 1.13 g (2.42 mmol, 85%, based on (C ₂ F ₅ ) ₂ BiCl).
Decomposition point:> 200 ° C.

Example 7: Diels-Alder reaction catalyzed by bismuth (III)

Diels-Alder reaction of maleic anhydride and 1,3-cyclohexadiene to give 3 ', 4,7,7'-tetrahydro-4,7-ethaneisobenzofuran-1,3-dione is obtained by using dichloromethane as a solvent. In room temperature. The solution becomes lemon yellow rapidly as the color becomes weaker during the reaction. The following table shows the reaction conditions, weights, and volumes of the starting materials and catalysts.
The results confirm that (C ₂ F ₅ ) BiCl ₂ and (C ₂ F ₅ ) ₂ BiCl are much more active catalysts in the Diels-Alder reaction compared to BiCl ₃ .

Example 8: Cyanosilylation catalyzed by tris (pentafluoroethyl) bismutan, Bi (C ₂ F ₅ ) ₃ ).

Cyanosilylation of trimethylcyanide using benzaldehyde to give 2-phenyl-2- (trimethylsiloxy) acetonitrile is CH ₂ Cl ₂ or 1-ethyl-3-methylimidazolium tris (ethyl pentafluoride) trifluoro as solvent. Run in phosphate (EMIM FAP) at room temperature. The table below shows the reaction conditions, weights, and volumes of the starting materials and catalysts.

This result, by _{(C 2} F ₅₎ good solubility 3 Bi of a hydrophobic ionic liquid, the catalytic activity in the _{EMIM FAP (C 2 F 5)} 3 Bi in conventional organic solvents, For example, it shows a significant increase compared to CH ₂ Cl ₂ .

Claims (11)

Use of at least one compound of formula (I):

M here represents, in each case, independently of one another, 2, 3 or 4;
n represents 1, 2, or 3; and
X represents F, Cl, Br, or OSO ₂ CF ₃ as a Lewis acid catalyst. Formula perfluoroalkyl group in _{(I) (C m F 2m} + 1) is the same in each occurrence, Use according to claim 1.   Use according to claim 1 or 2, wherein m represents 2 or 4.   4. Use according to any one of claims 1 to 3, wherein X represents Cl. Compound of formula (I):

M here represents, in each case, independently of one another, 2, 3 or 4;
n represents 1 or 2; and
X represents F, Cl, Br, or OSO ₂ CF ₃ .   6. A compound according to claim 5, characterized in that X represents Cl. Process for the preparation of a compound of formula (I) according to any one of claims 1 to 3, characterized in that n represents 3, characterized by a compound of formula (II):

Wherein m represents 2, 3, or 4 and reacts with bismuth trichloride, bismuth tribromide, or bismastristriflate, and the reaction conditions are such that the water content and oxygen content are at most 100 ppm. Selected. Process for the preparation of a compound according to claim 5 or 6, characterized by a compound of formula (II):

Where m represents 2, 3 or 4 independently of each other in each case and in the first reaction reacts with dichloroarylbismutan or chloro (diaryl) bismutan, where in the corresponding bismutan Aryl has 6 to 10 carbon atoms (which may be substituted or unsubstituted) and is of formula (IIIa) or (IIIb)

The intermediate of is then reacted with hydrogen chloride, hydrogen bromide, anhydrous HF, or CF ₃ SO ₃ H to give a compound of formula (I), wherein Ar in each case, independently of each other, Denotes an aryl group having 6 to 10 carbon atoms (which may be substituted or unsubstituted), wherein the conditions for the reaction with the compound of formula (II) are the water content, and also the oxygen content The maximum is 100 ppm.   Condensation reaction, alcoholysis, aldol reaction, mukaiyama aldol reaction, gutterman-koch reaction, Beckmann- and fries rearrangement, Friedel-craft acylation, Friedel-craft alkylation, Mannich reaction, Diels-Alder reaction, azadirs-Alder reaction , Baylis-Hillman reaction, Reformatsky reaction, Claisen rearrangement, Pruss cyclization reaction, allylation of carbonyl compounds, cyanation of aldehydes and ketones, cyanosilylation of aldehydes and ketones, 1,3-dipolar cycloaddition, or Michael 5. Lewis acid catalyst according to claims 1-4 for use in a Lewis acid catalyzed reaction selected from reactions. Compounds of formula (IIIa) and (IIIb)

Where m independently of one another represents 2, 3 or 4 in each case; and
Ar in each case, independently of one another, represents an aryl group having 6 to 10 carbon atoms, which may be substituted.   Use of at least one compound according to claim 10 as a Lewis acid catalyst.